The pandemic coronavirus disease 2019 () is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). As the first step of the viral replication, the virus attaches to the host cell surface before entering the cell. The viral Spike protein recognizes and attaches to the Angiotensin-Converting Enzyme 2 (ACE2) receptor found on the surface of type I and II pneumocytes, endothelial cells, and ciliated bronchial epithelial cells. Drugs targeting the interaction between the Spike protein and ACE2 may offer protection against the viral infection.
A variant called B.1.351 was first identified in the fall of 2020 in the Republic of South Africa. This South African variant, also known as 501Y.V2, has many mutations that may lead to higher transmissibility and infectivity. The Spike (B.1.351 Variant) (SARS-CoV-2) Pseudotyped Lentivirus were produced with SARS-CoV-2 B.1.351 Variant Spike (Genbank Accession #QHD43416.1 with B.1.351 mutations; see below for details) as the envelope glycoproteins instead of the commonly used VSV-G. These pseudovirions contain the enhanced green fluorescent protein (eGFP) gene driven by a CMV promoter, therefore, the spike-mediated cell entry can be determined via eGFP fluorescence. The Spike (B.1.351 Variant) (SARS-CoV-2) Pseudotyped Lentivirus can be used to measure the activity of neutralizing antibody against SARS-CoV-2 (B.1.351) variant in a Biosafety Level 2 facility.